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minutes_equal () determines whether the minutes of a given time is equal to the minutes of a second given time, ignoring the hours and seconds of both times. |
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hours_equal () determines whether the hours of a given time is equal to the hours of a second given time, ignoring the seconds and minutes of both times. |
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time_equal () determines the equality of two times. |
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time_not_equal () determines whether a given time is not equal to a second given time, in the sense that the first time contains a value of hours, minutes, or seconds that is not the same as the hours, minutes, or seconds of the second time. |
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time_greater () determines whether a given time is greater than a second given time, in the sense that the first time occurs after the second time. |
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time_less () determines whether a given time is less than a second given time, in the sense that the first time occurs before the second time. |
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time_greater_or_equal () determines whether a given time is greater than or equal to a second given time, in the sense that the first time either occurs after the second time or is the same time. |
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time_less_or_equal () determines whether a given time is less than or equal to a second given time, in the sense that the first time either occurs before the second time or is the same time. |
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These functions perform the basic validations for the Western calendar. The Gregorian and Julian validations are strict, in the sense that they consider date ranges and cannot be used proleptically. |
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valid_date_gregorian () determines whether a date is valid within the Gregorian calendar system. |
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valid_date_julian () determines whether a date is valid within the Julian calendar system. It is proleptic backward, but not forward past 04 October 1582. |
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valid_time_24 () determines whether a time is valid within the 24-hour clock system. |
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The time validation function is arbitrary in several regards. First, it only accepts 0 for the hour of midnight, not 24. Second, it does not allow for leap seconds. Third, it assumes a 24-hour clock. |
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5.6.4
Date/Time Stamping and Compression |
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Stamping and compression routines are often used to compress dates and times to occupy smaller amounts of space. The compressed form may be used to stamp records with date and/or time information. Compression is often used to reduce storage space |
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